adapter: Add ConnectDevice method

This allows to connect device without doing general discovery. This is needed for some of qualification tests where there is no general discovery upfront and we need to do connection to device with provided address.

Another usecase is for scenario where scanning happen on one controller but connection handling on another.

New device object is announced only if physical connection was successful. On success this method returns path to created device object. After ConnectProfile return bluetoothd continue with services discovery and profile connection.

This patch implements bare minimum properties needed for connection -address and address type. If needed eg. for non-NFC based OOB it could be extended with more options.